Eleven Senate Democrats called Wednesday for Sen. Al Franken to resign amid mounting allegations of sexual harassment, raising the possibility he will become the second lawmaker to step aside over recent accusations of inappropriate behaviour.

Franken’s office said he would make an announcement about his political future on Thursday. No other details were provided.

In a campaign started by Democratic women, nearly a dozen senators said Franken should leave Capitol Hill. Franken faces multiple accusations of inappropriate touching and unwanted advances. He has denied intentional wrongdoing and has apologized.

In a lengthy statement posted on Facebook, Sen. Kirsten Gillibrand of New York said she was “shocked” and “disappointed” by several women’s allegations that Franken inappropriately touched them. She was joined by Sens. Mazie Hirono of Hawaii, Claire McCaskill of Missouri, Maggie Hassan of New Hampshire, Kamala Harris of California, Tammy Baldwin of Wisconsin, Debbie Stabenow of Michigan and Patty Murray of Washington, the highest-ranking woman among Senate Democrats, along with Joe Donnelly of Indiana, Robert Casey of Pennsylvania and Sherrod Brown of Ohio.

“While Senator Franken is entitled to have the Ethics Committee conclude its review, I believe it would be better for our country if he sent a clear message that any kind of mistreatment of women in our society isn’t acceptable by stepping aside to let someone else serve,” Gillibrand wrote.

If he resigns, Franken would be the second member of Congress to step aside during a recent reckoning over sexual harassment on Capitol Hill. Facing multiple accusations of inappropriate behavior around female aides, Rep. John Conyers, D-Mich., stepped down on Tuesday after more than half a century in Congress.

Franken has said he will cooperate with an ongoing investigation by the Senate Ethics Committee.

Any kind of mistreatment of women in our society isn't acceptable

In recent days, the Democratic women senators had spoken privately among themselves about the situation, agreeing that they could not tolerate Franken’s presence as allegations continued trickling out.

“People were at the edge of their patience with this. They’d had enough. One more allegation was going to be it,” said one senior aide, who was granted anonymity to describe private deliberations.

A second Senate aide familiar with the talks confirmed the private discussions among female senators.

Describing the mood among Senate Democrats, the aide said, “It’s a s—-y day.”

If Franken resigns, Minnesota Gov. Mark Dayton, a Democrat, would pick his replacement, who would serve until a November 2018 special election to fill the final two years of Franken’s term.